I think I'm reiterating what a couple of people said better than how I will, but it's my honest answer so I'll put it up.
Roddenberry had a fixed plan when he created Trek, and he personal chose Brana to continue that plan. And it shows. Some of the shows were considered risky in the mid to late nineties, because ethics, morality and equality weren't sexy. Which is funny, 'cos what's really risky is doing the same thing in the mid sixties when racial and sexual equality was on paper, but pretty much nowhere else.
Brana took that and ran with it. I grew up Catholic, so I'm not really fond of having parables and cheesy stories crammed down my throat. I never felt that was the case with Trek. It was space,Cool. Aliens,Cool. Plot,Cool. And a rare thing in the competitive world of tv ratings, a message that would have actually discouraged bigots from watching, Very Cool.